Automatic document feed type electrophotographic copying machine

Abstract

An electrophotographic copying machine comprises a document intake/return member for taking in each one of the document papers to the copying machine to conduct a copy operation, a document transport member for transporting a single document paper between the document intake/return member and a light scanning portion to provide an electrostatic latent image, a document exhaust member for exhausting the single document paper on an outside tray after being copied, and a mode selector for selecting the document transport member to forward the single document paper from the light scanning portion to the document exhaust member or return the same from the light scanning portion to the document intake/return member.

What is claimed is: 
     
       1. An automatic document feed system for an electrophotographic copying machine comprising: a document intake/return means for sequentially introducing document papers to the copying machine to be copied and returning the document papers which have been copied;   document transport means operable to rotate in a forward and reverse direction, said document transport means being responsive to said document intake/return means for transporting a single document paper between both said document intake/return means and a light scanning portion of the copying machine to produce an electrostatic latent image;   document exhaust means responsive to said document transport means for removing a single document paper which has been copied from the document transport means, and   mode selecting means operatively associated with said document transport means for selecting said document transport means to either forward the single document paper from said light scanning portion to said document exhaust means or return said document paper from said light scanning portion to said document intake/return means.   
     
     
       2. The apparatus of claim 1, wherein said document intake/return means comprises a movable flapper for selectively guiding the single document paper from said document intake means to said document transport means and from said document transport means to said document return means. 
     
     
       3. The apparatus of claim 1, wherein said document transport means comprises a belt extending over the area between said document intake/return means and said document exhaust means. 
     
     
       4. The apparatus of claim 1, wherein said mode selecting means includes first and second manual switches. 
     
     
       5. The apparatus of claim 1, wherein said document intake/return means comprises at least three rollers which are operable to rotate in a forward and reverse direction according to the modes selected by said mode selecting means. 
     
     
       6. The apparatus of claim 1, wherein said document intake/return means comprises document return sensor means for detecting the return of the document paper to said return means. 
     
     
       7. The apparatus of claim 1, wherein a feed tray is provided adjacent the document intake/return means for receiving the document paper. 
     
     
       8. The apparatus of claim 1, wherein an exhaust tray is provided adjacent the document exhaust means for receiving the document paper. 
     
     
       9. The apparatus of claim 1, wherein the document intake/return means includes, on the inlet side thereof, a feed roller, pick-up roller and return roller in stacked relationship and on the outlet side thereof a pair of opposite rollers with a moveable flapper disposed therebetween and sensor means disposed on the inlet side of said return roller for rotating said movable flapper when contacted by the document paper returning to the document return means.